By the year 1517, 25 years after Christopher Columbus discovered the New World, most of the Atlantic coasts of both North and South America had been sighted and reasonably well surveyed. Most of the islands of the Caribbean had been colonized by the Spaniards, and northern South America and the Caribbean coast of Central America, from Panama to Honduras, had been explored and mapped. Four years earlier, in 1513, Vasco Nuñlboa had reached the Pacific Ocean by crossing the isthmus of Panama, but the search for a sea route to the Pacific and to the fabulous kingdoms of the Orient, the original objective of Columbus' had not yet met with success. The great Gulf of Mexico—the “Sinus Mexicanus” of many old maps— also remained unknown, and there was considerable confusion concerning which of the discovered lands were islands and which were parts of the mainland.
Juan Ponce de Leon, in his search for the legendary fountain that would restore youth to old men, had explored in 1513 the east coast of the Florida Peninsula as far north as the present location of St. Augustine, but had only ventured a short distance north along the west coast. He was convinced that he had discovered an immense island. Diego Miruelo, in 1516, explored the east coast of Florida and seems to also have sailed some distance along the west coast of the peninsula. But neither Ponce de Leon nor Miruelo realized they had sailed into the entrance to a vast gulf or
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The Gulf of Mexico Basin
Eighteen chapters deal with the entire Gulf of Mexico basin. Included are significant contributions from Mexican geologists. Nine topical chapters cover regional aspects of physiography and bathymetry, structural framework, the basement crust, salt tectonics and listric faulting, igneous activity, seismic stratigraphy, oil and gas resources, mineral resources and geopressured-geothermal energy, and ground water. Six chapters summarize regional stratigraphy and paleogeography for the pre-Triassic, Triassic-Jurassic, Lower Cretaceous, Upper Cretaceous, Cenozoic, and late Quaternary. Also included is a synthesis of the origin and development of the Gulf of Mexico basin. Six 4-color plates summarize the bathymetry, natural resources, tectonics, and basement structure and subcrop of the region, and provide a stratigraphic correlation chart and geologic cross sections.